It is well known that integrated circuit chips are becoming increasingly complex with correspondingly crowded circuit architectures. However, such crowded architectures often result in an unwanted increase in heat generation. For example, some integrated circuit chips currently generate as much as 40-50 watts of power on a 1-inch by 1-inch surface. The excess heat generated by such chips will destroy or burn-up the chip if not removed. Thus heat sinks are commonly attached to the chips to remove excess heat.
As shown in Prior Art FIG. 1, a heat sink 10 is often directly attached to the printed circuit board 12 on which a chip 14 is mounted. Heat sink 10 is attached to printed circuit board 12 using one or more screws 16a-16d. The screws 16a-16d are inserted from the back surface of printed circuit board 12 and are screwed into heat sink 10 residing on the front surface of printed circuit board 12.
However, prior art heat sinks are typically bulky, unwieldy, and completely prevent access to the chip. Access to the chip is repeatedly required, for example, for repair, testing, or replacement of the chip. Furthermore, many computer systems and test consoles have access ports built therein to provide access to chip. However, as shown in Prior Art FIG. 1, heat sink 10 cannot be removed from chip 14 without first unscrewing screws 16a-16d. Thus, the back surface of printed circuit board 12 must be accessed to unscrew screws 16a-16d holding the heat sink in place. Thus, the access ports are not always useful.
Furthermore, in many instances, very little space is present near the back surface of the printed circuit board. In such instances, the entire printed circuit board must be removed to gain access to the screws. Removing the entire printed circuit board is a time consuming task which is inconvenient and which costs money in wasted man-hours.
As an additional drawback, screws used in prior art systems do not always uniformly attach the heat sink to the chip. That is, if all of the screws are not tightened to the same extent, the heat sink may not uniformly contact the surface of the chip.
Thus, a need exists for a heat sink unit or assembly which can be attached to or detached from a chip without accessing the back surface of the printed circuit board on which the chip is mounted. A further need exists for a heat sink unit or assembly which insures uniform contact between a chip and a heat sink.